The present invention relates to the field of energy and is directed to a child-proof lighter, i.e. the lighter provided with a means for neutralizing ignition elements being movable between an operating neutralizing position wherein no spark is struck on activating an ignition device, and a position wherein it is possible to produce a spark required to ignite the gas.
Lighters of this type are known which are described in GB, No.A-2304879, U.S. Pat. Nos. 5,096,414, 5,547,370, 5,868,561 in which a gas ignition device includes a corrugated wheel positioned on a shaft and firmly connected with it, gearwheels rotatably positioned on said shaft by the sides of the corrugated wheel, a flint spring pressed toward the corrugated wheel, whereby said shaft has side portions on which these gearwheels are located and formed as a polyhedron, and end portions which are cylindrical and disposed in openings of brackets of the lighter body. A maximum diameter of the shaft in the area where the gearwheels are mounted is less than a minimum diameter of the openings of these wheels.
When the corrugated wheels are classically acted upon, the latter turn about the shaft which precludes striking a spark since the corrugated wheel will not rotate. To ignite the gas exiting the lighter burner valve, it is necessary to depress the gearwheels, to force them into contact with the shaft edges and to turn the wheels in conventional manner. Due to friction appearing when the gearwheels and the shaft interact in the contact area, the shaft and the corrugated wheel sitting on it can turn.
Safety devices described in the patents do not require any additional buttons and lever movements in order to achieve the goal which makes them more attractive as compared to other lighters. The only thing required from a user is to more attentively and with a certain force to depress the gearwheels, otherwise they would rotate idly.
However, due to the fact that the gearwheels rotate about the shaft independently of one another, the user not always is able to select the force needed to turn the corrugated wheel. In certain cases, the both gearwheels operate in time but sometimes, only one. Therefore, the user now easily lights the lighter, now with some difficulty.
With all classical lighters, the spark striking device is of an integral design. The above-mentioned inventions lack this feature. Here the spark striking wheel consists of a plurality of loosely interconnected parts. This complicates the process of assembling and repairing the lighter, and in the event the lighter drops, there is a risk to lose some parts.
A gas lighter is known from EP, No. 0752559 having a safety device designed to prevent the possibility of children igniting the lighter, which lighter comprises a gas ignition device including a corrugated wheel secured to a shaft rotatably and movably mounted in profiled openings of body brackets, a flint spring pressed toward the corrugated wheel. In these lighters, the shaft of the corrugated wheels is mounted in the profiled openings of the body brackets and is movable along a direction which is perpendicular to a direction of action of the flint spring. The profiled opening is a shaped slot in which, in a first position at one slot wall a rotation axis of the shaft of the corrugated wheel extends through a line coinciding with the direction of action of the flint spring, while in a second position at a slot wall from the side opposite the burner valve location, the rotation axis of the shaft of the corrugated wheel is biased relative to said line. Whereby, in the second position at the other slot wall from the side opposite to the burner valve location, the corrugated wheel is spring pressed from the side of the flint in a direction tangential to the outer surface of the corrugated wheel.
Operational reliability and durability of such a lighter are determined by the state of the shaped slot. Unless the shape of this slot is not changed the lighter implements its function of preventing children from using it. When the slot shape is changed, fixation of the shaft of the corrugated wheel in extreme positions of the slot is broken. In the known lighter, the shaft of the corrugated wheel is triangular in cross-section, while the body brackets are made from a polymer the hardness of which is substantially less than that of steel of which the shaft of the corrugated wheel is made. When the shaft with triangular cross-section moves along the walls of shaped slot, the shaft edges forcefully act on the slot walls and deform them, which results in changing the shape of the slot itself, due to which the shaft of the corrugated wheel within the slot may occupy not only two fixed positions corresponding to the lighter operating position and neutralization mode, but also intermediate positions from which this shaft can easily jump to a neutralization removal position.
Based on the foregoing, it is possible to formulate a number of requirements compliance with which would allow to enhance the operational indicators of the gas lighter with safety device, the main of which is increased reliability of the safety device.